Heater



H. s. DODD.

HEATER.

APPLICATION FILED MAY I4. 1918. A

Patented Apr. 19, 1921.

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HENRY S. DODD, OF TORONTO, ONTARO, CANADA, ASSIGNOR 0F ONE-HALF TO JOHN ONEILL, OF TORONTO, ONTARIO, CANADA.

HEATER.

' Specification of Letters Patent.

Patented npr. i9, m21.

Application filedMay 14,1918. SerialvNo. 234,563.

To all whom t may concern:

Be it known that l, HENRY STANsrIELD lione, or' 313 Eglinton avenue, in the city of Toronto, county of York, Province of Ontario, Canada, a subject of the King of Great Britain, have invented certain new and useful Improvements in Heaters, of which the following is a specication.

This invention relates to heaters particularly adapted for lthe heating of a circulating fluid such as air or water, or for the generation et steam, and my object is to devise a heater for this purpose in which a gaseous fuel can be economically used.

l attain my objectvby means orp the constructions hereinafter described and illustrated in the accompanying drawings in whichl l Figure 1 is a vertical section of Ya heater constructed in accordance with my inven tion; and

Fig. 2V a cross section on the line a-a in Fig. l; and A Fig. 3 a vertical section showing a modilication of the closure 4 shown in Fig. 1.

ln the drawings like numerals of reference indicate corresponding parts in the different figures.

rlhe device, as usual in heaters of this kind, employs a combustion chamber andV radiating system which, when a heating fluid is to be circulated^ is surrounded by a casing. The casing in the present construction is preferably formed in three sections 1, 2 and 3. The upper section is provided with the outlet 5 and the lower section with the inlet 6.' The middle section of the casing contains the combustion chamber 9, which is provided with a central tubular extension 42 which reaches up through the upper section and passes through an opening therein, a suitable tight joint being formed between the parts by the gland 41.

The upper end of the chamber 9 has a cover 10 with a pipe 40 connected therewith,

, which pipe is termed with an elbow havingv an opening in its end inclined somewhat from the vertical away 'from the hanging closure 4, which, when there is no suction in the combustion chamber, hangs straight down so that the products of combustion from the pilotflight may pass away. As soon as suction exists the light flap is drawn inwardly to close the opening. A suitable flue 50 is connected with this pipe.

Through the side of the combustion chamber is formed a lateral extension communieating with a tube 34 extending through a boss 35 formed on the wall of the section 2 of the casing. A gland 36 is employed to prevent leakage around the tube, while permittlng endwise movement of the tube. The gland has an open end l1, provided with a transparent closure 7. Through the tube the pilot light may be lit. v 8 is readily had or the latter placed in position or removed by removing the cover 10 from lthe top of the combustion chamber. The under side ot the combustion chamber is preferably formed of a removable plate 12. The combustion chamber is provided with lugs 38 by means of which it is supported on lugs 39 formed on the lower part 3 of the casing, but is not secured thereto 1n any way.

The radiating system includes concentric tubes 13 and 14. The tubes 13 extend into openings in the top of the combustion cham-- ber leading to the yinterior of the upper section 1. The tubes 14 extend from the openings in the plate 12 to openings in the top of the header 15. The lower ends of the tubes 13 are connected with openings in the bottom oi: the header 15. The products of combustion thus pass from the combustion chamber between the inner and outer tubes into the header 15. Y From this header 15 ex tends the exhaust flue 16, which extends through the lower section 3 of the casing preferably concentric with the vertical axis of the heater.

through. which the exhaust flue passes is made water and steam tight by a suitable stuffing box 17. The object of this arrangement is to prevent any strain on the radiating system which would result in leakage. The radiating system, which includes the combustion chamber 9, tubular extension 10, tubes 13 and 14, header 15 and part of the exhaust flue 16, is subjected at times to sudden changes of temperature which causes its expansion or contraction more rapidly than the expansion or contraction of the casing, and as with the construction shown the radiating system is merely supported on the casing by means of the combustion chamber and is otherwise free, its expansion and contraction is quite independent of the contraction and expansion of the casing. The ex- Access to the burner' haust flue connects by means of the pipe 18 with an exhaust pump 19. When the device is in operation the pump is run to suck the burnt gases from the combustion chamber and radiating system of the heater. Very intense combustion then takes place in the combustion'chamber of the mixture of air and gas supplied to the burner and very rapid expansion of the productsof combustion at once takes place, resulting in a slight pressure in the combustion chamber'.

The spaces between the tubes are, however, sufficient in area to permit of the immediate expansion of these gases. Owing to the suction, combustion takes place not only in. the combustion chamber, but also in the spaces between the tubes where the greatest transfer of heat to the fluid to be heated will talre place. rlhe greatest diiference exists here between the temperature of the `duid to be heated and the heat transferring surfaces.

The fire tubes are comparatively long and compensation is thus obtained for vtheir small cross sectional area compared with that ofthe combustion chamber. By the time the products of combustion reach the exhaust flue outside the' casing they havey been cooled substantially to the temperature of the fluid entering the casing from the return pipe. yThe burner 8 is located within the combustion chamber as shown and may be of any form. lprefer, however, to employ a burner of cylindrical form havingl disk-shaped ends between which are set a series of bars between which a combustible mixture `passes and outside which it ignites. Connected with the interior of the burner is the supply pipe 21. rllhis passes down through the plate 12 and header 15 and through the exhaust Hue 16 and is provided at its end. with a connection 22.

Where the supply pipe passes through the elbow-shaped stutling box 17, a packing gland l23 is provided. rlhe gas is mixed with air in a mixing chamber 3() of which 31 is the air inlet and 32 the gas inlet. The flow of gas will be controlled by means of any suitable automatic valve A suitable valve for this purpose will be made the subject of a separate application. rlhe valve is connected to the suction pipe 18 by means ot the pipe 28. The purpose of the valve is to close off the gas supply whenever the suction ceases. The air inlet of the mixing chamber is connected by a pipe 24 with an air preheating chamber 25 surrounding the pipe 18. The space between the pipe and chamber is preferably provided with a spiral or other baffle 26 to cause the air to travel over as much of the surface of the warm pipe 18 as possible. i

Gas to supply a pilot light may be led vthrough a tubev27 which extends through a Asupply pipe 21 and extends into the interior of the burnerwhere it isl provided with one or more branches 47 extending to the outside of the burner at one or more points.

f 1n burning gas, water vapor is one of the products of combustion and provision must be made for its removal fromnthe radiating system of the heater. For this purpose l provide the pipe 57 leading from the stuliing box 17, which pipe will be suitably trapped.

As the Huid returning to the casing through the return pipe 6 will seldom give a temperature of less than 160O Fahr. the exhaustgases will have at least the same temperature. @wing to the fact that l use a pump 19 to exhaust the gases from the heater, 1 am enabled to circulate these exhaust gases through a radiating coil 56 from which the remaining heat units are readily extracted and employed forjheating or ventilating purposes.

l/Vhen the heater is running and the burner alight, all the air required for the combustion of the gas is sucked Vthrough the mixing chamber 30. lWhen the burner is out, the pump is stopped but sufficient air is drawn through by natural draft to maintain the pilot light at the branches -47.

A simple hanging closure such as shown in llig. 1 does not 'always provide free enough exit for burnt gases and is somewhat liable to damage. 1 prefer therefore to use the specific construction shown in Fig. 8, which is identical, however7 in mode yof op` eration. The closure is formed as a plate 4CL adapted to seat on the opening 43 in the cover 10. A yoke 44 is suitably supported above the opening and carries the counterf nected the connectingrod 46, which passes loosely through an opening in the plate 4a and has a ball 58 formed at its lowerV end. The lever 45 is so weighted that normally it will raise the plate 4a, but the balance will be so delicate that the plate is easilyV drawn down again when suction exists in the apparatus.l lf any explosion of gases takes place in the heater, this plate is driven up the connecting rod and free yexit for the gases is provided. lt will be noted that comparatively small liftof the plate gives a very free exit for the products of combustion fromthe pilotlight.

My apparatus in operation .is found to be exceedingly economical. lt is also easily constructed and veasily taken apart for repairs. y

Vlhat l claim as my invention is 1. A heater comprising a casing, an air pump, a combustion chamber located at one end of the casing above the bottom thereof, a radiating system with which the combustion chamber communicates and from which the products of combustion are drawn by the air pump comprising a header locatedtoward the other end of the casing, a plurality of fire tubes opening through the bottom of the combustion chamber below the burner and connecting the combustion chamber and the header, an exhaust Hue extending from the header through the adjacent end of the casing, a tube extending laterally from the combustion chamber through the side of the casing, a suitable closure for the outer end of the tube, the exhaust Hue arranged axially of the header and provided with a stuffing box in the end of the casing through which the exhaust Hue passes, and a supply pipe to the burner extending axially through the exhaust Hue and passing through the wall of the Hue outside the casing.

2. A heater co-mprising a casing, an air pump, a combustion chamber located at one end of the casing above the bottom thereof, a radiating system with which the combustion chamber communicates and from which the products of combustion are drawn by the air pump comprising a header located toward the other end of the casing, a plurality of Hre tubes vopening through the bottomof the combustion chamber below the burner and connecting the combustion chamber and the header, an exhaust Hue extending from the header through the adjacent end of the casing, a tube extending laterally from the combustion chamber through the side of the casing, a suitable closure for the outer end of the tube, the exhaust Hue arranged axially of the header and turned at an angle outside of the casing, and provided with a stuffing box in the end of the casing through which the exhaust Hue passes, al supply pipe to the burner extending axially through-the exhaust Hue, and a stuffing box, located in the wall of the Hue at the bend, through which the supply pipe passes.

3. A heater comprising a casing, an air pump, a combustion chamber located at one end of thecasing above the bottom thereof, a radiating system with which the combustion chamber communicates and romwhich the products of combustion are drawn by the air pump comprising a headerlocated toward the other end of the casing, a plurality of fire tubes opening through the bottom of the combustion chamber below the burner and connecting the combustion chamber and the header, an exhaust Hue extending from the header through the adjacent end of the casing, a tube extending laterally from the combustion chamber through the side of the casing, a suitable closure for the outer end of the tube, a tubular extension of the combustion chamber extending through the end of the casing, and a removable closure for said extension, the burner being removable through said extension.

4C. A heater comprising a casing, an air pump, a combustion chamber locatedl at one end of the casing above the bottomthereof,

'the products of combustion are drawn by the air pump comprising a header locatedv toward the other end of the casing. a plurality of Hre tubes openingV through the bottom of the combustion chamber below the burner and connecting the combustion chamber and the header, an exhaust Hue extending from the header through the adjacent end of the casing, a tube extending laterally from the combustion chamber through the side oi' the casing, a suitable closure for the outer end of the tube, the casing being divided into three or more horizontal sections, the middle section containing the combustion chamber and in which the combustion chamber is providedy with a part extending through the end of the upper section and with a suitable removable closure for the upper end of said part.`

5. A heater comprising a casing divided into three sections; a combustion chamber contained in the middle section and provided with lugs, the lower section being provided with lugs at its upper end on which the Vlugs of the combustion chamber rest; an upward extension -of the combustion chamber extending through the top of the upper section and provided with a suitable closure; a fuel burner located within the combustion chamber; and a radiating system with which the combustion chamber communicates and from which the products of combustion are drawn by an air pump comprising a header located toward the other end of the casing; a plurality of Hre ytubes connecting the combustion chamber and the header and an exhaust Hue extending from the header through the adjacent end of the casing.

6. In a heater, the 'combination of a casing for the Huid to be heated provided with an. inlet and outlet; and a radiating system within the casing freely suspended on the casing so as to be free' to expand laterally, the said radiating system including a combustion chamber adjacent its upper end, an upward extension of the combustion chamber passing through the upper end of `the casing and an exhaust Hue extending down through the lower end of the casing; and stuffing boxes adapted to make tight joints where the exhaust Hue and the extension pass through the casing.

7 In a heater, the combination of a casing comprising a lower, an intermediate and lugs aforesaid; an inspection tube extending from the side of the combustion chamber and passing through the side of the intermediate section; and a Stutling box adapted to make a tight joint Where the tube passes through said section.

8. in a'heater, the combination of a casing 'for the i'luid to be heated provided With an inlet and an outlet; a combustion chamber Within the casing freely suspended on the casing; an inspection tube extending from the side of the combustion chamber and passing through the side of the intermediate section; and a stufling box adapted to make a tight joint Where the tube passes through said section.

9. 1n. a heater, the combination oi' a casing for the fluid to be heated provided with an inlet and an outlet; a combustion chamber Within the casing freely suspended on the casing; an inspection tube extending from the side of the combustion chamber and passing through the side of the intermediate section; a stuiiing box adapted to make a tight joint Where the tube passes through said section; and a transparent closure for the open end of the stui'hng box.

10. A heater comprising a casing, an air pump, a combustion chamber located at one end of the casing above the bottom thereof,

tion chamber communicates and from which the products of combustion are drawn bythe air pump comprising a header located toward the other end ofthe casing, a plurality of lire tubes opening through the bottom of the combustion chamber below the burner and connecting the combustion chamber and the header, an exhaust flue extending from the header through' the adjacent end of tie casing, a tube extending laterally from the combustion chamber through the side of the casing, a suitable closure for the outer end of the tube, a tubular extension ot' the combustion chamber extending through the end of the casing, a removable closure for said extension, the burner being remov-V HENRY s. noun. 

